Tempo Koban
The Tempo Koban was minted between 1837 and1858. The gold koban
(ryo) was the highest value coin in circulation. Koban
were first minted in the Keicho Era around 1601. While the weight
of ten Koban equalled on Oban, the buying power of only seven Koban
was necessary to equal the buying power of one Oban.
